I miss my ex but..

I was talking to a guy friend that I barely even talk to anymore over Snapchat, and he said he missed me as in being close friends like we used to. So we were talking and I sent him a grade 8 photo of us and then a recent photo we took before he moved and then he said “we were cute tho” and I said “hell yes.” Then he said “stop with the periods makes you seem mad” LOL so I screenshot that and put it on my story but blocked out the photo and his name. Then my ex snapped me back saying “new mans” “I ain’t stupid I know that’s a guy” “you’re being sketch, peace” and I literally said nothing then he blocked me on there. Me and my ex just recently started talking again but only as friends and we were talking about getting back together but then he called me a joke and when I tried explaining to him what me and my friend were talking about he straight up just said “ I DONT GIVE A FUCK”

Like what did I do wrong :( i feel so hurt and confused. I just feel like I’m doing everything I’m not supposed to and not even realizing it. I need help and advise